We investigated the effect of polymer dispersed liquid crystal (PDLC) layer thickness on morphology and electro-optical properties of plastic UV-curable PDLC films with two nematic liquid crystal mixtures TNO623 and TNO403. The PDLC films were prepared on flexible Indium Tin Oxide (ITO) coated Poly-Ethylene-Terephthalide (PET) supports by UV-polymerization induced phase separation, and the uniform film thickness was insured by plastic micro-spacers. We found that the PDLC layer thickness at the same morphology effects on electro-optical properties of off-state and on-state transmissions, switching voltages and response times.